Checking around the Googlesphere, I found a number of articles describing his season with Seattle, and that he was in Spring Training with the Angels before he was sent down. Nothing, though on any deal, until the always-reliable Toledo Blade came through. From the Oct. 17, 1966 paper:

"The Cleveland Indians traded infielder George Banks to the California Angels for outfielder Willie Smith yesterday."

Willie Smith! One of the all-time favorites from the 1969 Cubs, and a successful pitcher early in his career that switched to an outfielder/pinch-hitting specialist. Checking his Baseball Reference major league page, we find the following transaction listed: